| Autor: |
Alain Wattiaux, M. Deus Carvalho, J.P. Loup, P. Odier, C. Allançon, Jean-Marc Bassat |
| Rok vydání: |
1998 |
| Předmět: |
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| Zdroj: |
European Journal of Solid State and Inorganic Chemistry. 35:173-188 |
| ISSN: |
0992-4361 |
| DOI: |
10.1016/s0992-4361(98)80195-1 |
| Popis: |
Two synthesis methods for preparing Pr 4 Ni 3 O 10±δ are compared : a modified sol — gel route and a nitrate — citrate one. It is shown that the autoignition involved in the nitrate — citrate route provides good conditions ressembling the Rapid Thermal Annealing procedure. The oxygen stoichiometry of Pr 4 Ni 3 O 10±δ phases is measured according to the method of synthesis and thermal treatment. The compounds are metallic as seen by electrical resistivity measurements and thermoelectric power. We show that the adjustment of δ in this series is an important parameter of the transport properties that change from metallic for −0.1 4 Ni 3 O 8.25 . An electronic anomaly is evidenced at 160 K, which intensity is more marked for the stoichiometric Pr 4 Ni 3 O 10 . Our results are consistent with the existence of a charge density wave instability. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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